Night Eating After Gastric Bypass

Roux-en-Y gastric bypass surgery (RYGBS) reduces the size of the stomach for morbidly obese persons who have been unable to lose weight by other means. Although binge eating often disappears after this procedure, probably due to a smaller stomach capacity, night eating often persists.

Dr. Marci E. Gluck and colleagues at New York Obesity Research Center, New York, NY, St. Luke’s/Roosevelt Hospital, Glen Cove Hospital and North Shore Long Island Jewish Health System asked 24 morbidly obese patients to complete the Night Eating Diagnostic Questionnaire based on the work of Dr. Albert Stunkard (Int J Obes Relat Metab Disord 1996;20:1)before surgery. Two patients were male, and 22 were female. The test showed that 10 were night eaters, while 14 were not night eaters. The authors also assessed depression, restrained and external eating, self-esteem, ideal body image and discrepancy in body image. The subjects were divided into two groups, the night eaters and non-night eaters (controls).

Then, prior to a fixed meal, stress and hunger were rated and cortisol levels were measured. Before surgery, there were no significant differences between the two groups in body mass index (BMI; kg/m2), cortisol levels, stress ratings, or results on psychological tests. Hunger ratings were lower in the night eaters group than in those who were not night eaters.

What follow-up tests showed

Eleven of the subjects (4 night eaters and 7 non night eaters) returned for their 5-month follow-up, and the presurgical tests were repeated. The percentage of weight loss did not differ between the two groups, based on night-eating status at baseline, and there were no differences between the groups in changes in depression or restrained eating. However, those who were classified as night eaters at baseline had a significant increase in cortisol levels. The control group had a significant decrease in hunger ratings, a significant increase in ideal body shape ratings, and trends toward a greater decrease in external eating, body image discrepancy, and low self-esteem than did the night eaters.

The authors concluded that despite having the same weight loss as those who were not night eaters, the night eaters had increased cortisol levels and less improvement in psychopathology after RYGBS. They reported the results of their study at the Eating Disorders Research Society meeting in Toronto last fall.